Does damage from the AoO apply as a penalty to the Combat Maneuver roll as in pathfinder?

Good question! The answer is no, because most people already take wound penalties from injuries sustained from an AoO, and I didn't want them stacking. Probably I should spell that out somewhere in the rules.

Kaylissa will save: 1d20 + 5 ⇒ (7) + 5 = 12
She shrugs off the spell as she would a gnat; you're not sure if it's because she's mentally that tough, or just too experienced to be taken in by that particular spell.

If that kills the zombie, and no other close ones remain, Kelgan will nod to Caspian, watch yourself, then advance 20 feet towards Kaylissa, avoiding the greased area. If he can get Wyvern in reach, will once again drop into shield ally.

The zombie drops. Avoiding the grease detours you out of the way, however, and prevents you from closing the distance to reach Wyvurn. Next turn you can easily move up to cover him and still attack Kaylissa or the other zombie, however.

Done! Wyvurn -- you are now protected by Kelgan. Kalgan -- Kaylissa sees this burst of valor on your part and her eyes widen -- it's clear she didn't think you could move into place that fast, and you can practically see her abortively stop a motion towards Wyvurn. You're pretty sure that your expediture of heroism just saved the hobgoblin's life.

Wolvie the Zombie Slayer crashes into the last zombie (Kaylissa's bodyguard), knocking it to the floor and savaging it with his fangs. Combines with the deep slash Wyvirn had already inflicted on the thing, it's now a goner.

For future ease of play, since Wolvie's trip only activates on a hit anyway -- and has the same bonus -- let's just use his attack roll as his trip roll as well.

The light in the basement is dim enough that Cricket is able to skulk in the shadows and begin edging around the room, hiding among crates and torture implements (!).

Kaylissa, devoid of bodyguards and unable to get in a quick kill on Wyvurn, and seeing the rest of you about to close in on her, raises her obsidian necklace and steps forward and to her right; she is now surrounded by combatants in an arc. The dark energy erupts forth:
3d6 ⇒ (5, 2, 1) = 8
Remember, DC 15 Will for half.

If I calculate correctly, she can just barely catch everyone after moving, but the movement puts her within Kelgan's 10-ft. reach, provoking an AoO from him as she goes past.

Wolvie starts mauling the prone and relatively helpless sergeant. She is now wounded, and doesn't look too happy at this development. Around savage barking and slobberings, when her throat is temporarily free from his teeth, she calls, "Well, kiss the Duke good-bye, boys!"

This interpretation would allow us to just have one save -- fewer dice rolls at the table. But then, if he had DR or energy resistance, as written that would also apply off the top, and you'd split the remainder, although it would be more "realistic" if it worked the other way -- you each took half, then each of your resistances, etc. applied to what each of you took. I'm open to suggestions and/or recommendations. How do you guys think it should work? We can have a vote and I'll amend the text accordingly, but let's move that discussion to HERE.

-4 for firing at a prone enemy, but she gets no Dex mod to AC...
Pretend the hero point was used to gain access to one combat feat for 1 round (a legitimate use). Say he picked ranged maneuver (disarm) as that feat...

If we go that route, the chunk of obsidian, struck by the sling ball, goes skittering off to the side before she can channel black doom on everyone again!

Or you can just hit her for 4 points of damage, with no observable effect except to annoy her slightly, and let her channel...